// add AbsFunction
generalFunctions.addAll((new AbsFunctionCluster()).getSupportedFunctions());
// add RoundFunction
generalFunctions.addAll((new RoundFunctionCluster()).getSupportedFunctions());
// add FloorFunction
generalFunctions.addAll((new FloorFunctionCluster()).getSupportedFunctions());
// add DateMathFunction
generalFunctions.addAll((new DateMathFunctionCluster()).getSupportedFunctions());
// add general functions from BagFunction
generalFunctions.addAll((new GeneralBagFunctionCluster()).getSupportedFunctions());
// add NumericConvertFunction